UNITED NATIONS / ADDIS ABABA - Top UN officials expressed concern on Sunday about escalating violence in the eastern Democratic Republic of the Congo (DRC).

"The situation is deteriorating rapidly," UN Assistant Secretary-General Joyce Msuya told an emergency meeting of the UN Security Council.

She said hundreds of civilians have been killed or injured in the last few weeks, and hundreds of thousands have fled their homes or shelters to escape gunfire and shelling.

Tensions have been running high due to the recent advances by the M23 rebels in North Kivu and South Kivu provinces. The rebels took control of Sake, a town considered the last defense for government forces before Goma, the capital of North Kivu and a major regional hub.

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Jean-Pierre Lacroix, UN undersecretary-general for peace operations, said the United Nations is profoundly concerned with the resumption of hostilities which have led to the loss of a strategic position several kilometers from Goma.

Stephane Dujarric, spokesman for UN Secretary-General Antonio Guterres, said the UN chief "is deeply concerned by the escalating violence in eastern DRC."

Guterres called for an immediate ceasefire. 

In Addis Ababa, Chairperson of the African Union Commission Moussa Faki Mahamat has expressed concern over the grave situation in the eastern DRC and called for an "immediate" cessation of all hostilities.

In a statement issued Saturday, the pan-African bloc said it is following "with great attention the deteriorating security and humanitarian situation" in the eastern DRC. The statement came as conflict intensifies and rebellion advances toward major townships in the eastern DRC.

Faki called for the strict observance of the ceasefire agreed between the parties and the immediate cessation of all hostilities. He further "strongly urged" the parties to preserve the lives of civilians.

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The chairperson also launched an urgent appeal to the international community to mobilize all possible support for the populations affected by the serious collateral damage of the expanding conflict in the eastern DRC.

The United Nations High Commissioner for Refugees said on Friday that more than 400,000 people have been displaced since the beginning of 2025 in the eastern DRC.

Expressing grave concern about the safety and security of civilians and internally displaced persons (IDPs) in the area, the UN refugee agency said persistent clashes between belligerents in the affected areas continue to worsen the protection environment for civilians in South Kivu and North Kivu provinces, which are already home to 4.6 million IDPs.